This entire scene is improbable, but every so often, I want this type of scene in a story or movie. Make it believable, for the story’s universe and I buy it.
From Inside the Grey House:
Natalia watched him go then made sure her backpack was securely on her back. She stood up and went to the edge of the balcony. She grabbed the top of the iron bar railing, lifted herself up and swung one leg, then the other over the top. Natalia turned to face into the balcony, gripped the bars very carefully and allowed herself to slide/drop to the balcony beneath her. Once her feet were on the edge of the railing, she let go of the balcony above her and jumped into the empty balcony without a problem. She took a few deep breaths then repeated the steps to end up on the first-floor balcony. From there, it was an easy jump to the ground.
On the ground, she hugged the wall, but ran quickly to the back of the building. At the corner of the building, she knelt down, looked around the corner, saw no one was around, stood and walked leisurely to her car. Once at her car, she opened the door, nodded to Charlie in the passenger seat, dug out her keys and started the car. They were out of the parking lot and well on their way before Natalia realized that Charlie was still staring at her in disbelief. She glanced at him out of the corner of her eye.